Polycomb Repressive Complex 1 Is Required to Maintain Stem Cell Identity and to Preserve Adult Tissue Homeostasis.

Polycomb Repressive Complex 1 (PRC1) was identified as crucial for maintaining stem cell identity and tissue homeostasis by repressing non-lineage specific transcription factors and controlling the WNT pathway, essential for stem cell self-renewal. The study highlighted that PRC1 loss in LGR5 expressing intestinal stem cells led to severe tissue maintenance defects, while in hair follicle stem cells, it activated a specific epidermal program, indicating tissue-specific transcriptional outcomes. The research also explored the complexity of PRC1, composed of various subunits forming different biochemical sub-complexes, and aimed to understand their roles in adult tissue maintenance using conditional knockout mouse models.